n teams in a football tournament
Source: Ukraine TST 2015 p2
May 2, 2020
combinatorics
Problem Statement
In a football tournament, teams play one round (). In each round should play pairs of teams that have not yet played. Schedule of each round takes place before its holding. For which smallest natural such that the following situation is possible:
after tours, making a schedule of rounds already is not possible,
i.e. these teams cannot be divided into pairs, in each of which there are teams that have not played in the previous rounds.PS. The 3 vertical dots notation in the first row, I do not know what it means.